U.S. Pat. Nos. 1,542,116; 3,675,670; 3,722,556; 3,897,807; 3,906,995; 3,989,059; 4,002,192 and 4,007,766 disclose the use of interconnected railway tank cars used to transport large quantities of liquid lading, particularly liquid petroleum, from place to place.
However, in many parts of the United States and elsewhere in the world, pipe lines and cargo ships are under construction which will reduce or eliminate the need for such interconnected tank cars. As an example, in the United States, pipe lines are presently under construction to transport liquid petroleum inland from the West Coast to Texas and Montana. When these pipe lines are completed, the need for interconnected tank cars to transport the liquid petroleum inland will be largely eliminated.
Tank cars which have been used in liquid petroleum service may then be used to transport other liquid lading.
However, tank cars are not generally suitable for the transport of particulate solid lading.
it would be desirable to provide an interconnectable railway car which is adaptable for use in unit-train service in transporting liquid lading such as liquid petroleum, and which is convertible to a railway car which is adapted to transport particulate solid lading when the car is not needed for liquid lading service.
U.S. Pat. Nos. 3,731,053 and 3,791,168, assigned to the same assignee as the present application, disclose openings in the end bulkheads of railway hopper cars and conduits in fluid communication with the openings for the purpose of circulating conditioned air within the hopper car. However, these patents do not disclose conduits interconnecting adjacent hopper cars for liquid lading unit-train service.
U.S. Pat. No. 3,918,604 discloses a cargo container which is convertible between liquid and granular material service. However, this convertible container does not disclose conduits interconnecting adjacent containers for liquid lading unit-train service.